When science journalist Bas Kast collapsed with chest pains when he was only 40, he was faced with an existential question: had he ruined his health with junk food? He decided to radically change his eating habits in order to heal himself. But what is really good for you? This was the beginning of a journey of discovery into the latest research into aging and nutrition – and it lasted several years. What do people with a particularly long life span eat? How can you lose weight efficiently? Are afflictions typical of old age avoidable? Can you "eat yourself young" with certain foods? Much of what we think is healthy can even be harmful. Bas Kast has filtered out from thousands of sometimes contradictory studies scientifically founded findings about what really makes for healthy eating.